My son and I are in need of help from you Camaro Gods out there. We are installing a '95 Camaro 3.4 L engine into a 1951 Jeep ******. He wanted a big V-8 but with gas prices and him being a new 16 year old driver I decided on a V-6. We reworked the engine mounts and the engine fits perfect. After getting past the theft prevention module first hurdle we got the engine to fire and run for a few seconds and stall. We replaced the fuel pressure regulator and it did improve things but we're still not there. After several attempts of the run for a few seconds and stall it appears to be getting warm and will all a sudden idle perfect and sit there and idle all day long. If we try to rev the engine quickly it dies on us. If we slowly increase the throttle it revs up nice and smooth. We think a sensor might be to blaim and are wondering which one to check on and if there are any sensors we can eliminate altogether. Being a 1951 vehicle we're not bothered by emission standards and dont have any of the charcole canister/fuel vapor sysyem hooked up. The purch selinoid doesnt have vacuum lines coming from this stuff to it. We are running straight pipes out the back through flow master mufflers. We have new plugs and wires installed. We are using the in tank fuel pump that came with the Camaro so fuel pressure is fine. Any help from you 3.4 L Camaro experts would be great.
Jeff and son Kevin

 

im not an expert, but i dont want ot see u travel the same path i have, just a bit of lessons i have learned from my current 3.4 stay away from straight pipe, and flowmaster. the flowmaster no matter what sounds good at an idle but drivin sounds likea ricer. open pipe well caused loss of power in my engine. again im not an expert, just throwin my lessons i have learned in a year with little piece.

 

If you're not using the emissions stuff, which the 3.4L computer will be looking for, why not just carb the 3.4L?

Bad thing about the 3.4L computer is that tuning software on the cheap is literally impossible to find en masse, so it's not like tuning the emissions components out of the ECM is practical...

Then again, I have heard that the MAP sensor (behind the throttle plate before the Y splits, I believe) will stall out the 3.4L if the hoses are leaking or disconnected...

 

How was the security module bypassed? If it is just removed and wired around, the computer will still try to shut down the injectors, unless is gets a coded message from the security module.

The PCM that comes with the engine does a bunch of things that are not involved with engine management. Probably what should be done, is to get the PCM reprogrammed to delete all the stuff you have taken out, including the security module, and to take into account what was done to the engine. If you do not have a local tuner shop, you can have the PCM programmed on an exchange basis. Give these people a call, their prices are usually reasonable and they will work with you.
www.pcmforless.com

 

We didn't remove the security module. We found out there are 10 different resistors used in the key and gave the module the resistence it was looking for. That got the engine to run and stay running. Without the right resistence like you said the injectors will shut down. We can get the engine to start and idle fine. It takes 4 or 5 trys starting before it stays running and idles. Once its idling we can increase the rpm's if we do it slowly. If we hit the throttle fast it dies. I dont know if the throtle position sensor, crankshaft position sensor, idle sensor, egr, mapp sensor or some other sensor could cause these symptoms. We really want to not go the carb route.

 

Have you checked the fuel pressure, being that it takes several tries to get going the fuel pressure may not be holding when the engine is off, or may just be too low, you need about 45 PSI with the vacuum line diconnected from the regulator. What fuel pump are you using? Do you have a vacuum line going to the press regulator?

 

We are using the original Camaro in-tank fuel pump. We didn't replace the filter on the end of the fuel pump since it looked pretty clean. I guess we could take that filter off as a test since we have an inline filter as well. Maybe its starved for fuel. We havent checked the fuel pressure with a gauge so we can do that. I've seen what looks to be a valve stem by the pressure regulator which should be the place to check check the pressure. We do disconnect the battery at night since we have alot of loose wires yet for lights/horns/ect and dont need a hot wire to short out and burn our house down. That could account for the hard starting. We did replace the pressure regulator which did seem to help. We still have the problem with once we get it running at a good steady idle it boogs down and dies if we try to accelaratetoo fast. I was wondering if we went to a KnN air intake it might help. There is a air temp sensor in the rubber elbow going into the throttle body which we tryed unplugging which seems to help as well. I'm not sure if this is something we need. I talked to the folks at pcmforless about reprogramming the pcm to take out the theft module and other emmisions stuff but for some reason no one does the 94-95 3.4 Litre Camaro PCM.

 

Check the fuel pressure at the valve on the fuel rail, se the procedure in the LT1 section. Some other things to check are the IAT sensor on the air intake, the ETC sensor, and the TPS on the throttle valve, also the MAP sensor could be giving false indications. It would be good to get a scan tool, not a plain code reader, and verify that what the PCM sees from the sensors makes sense. Also a possibility that the EGR is remaining open under load, you may want to remove it andclean it and the exhaust passage out.

 

Do you need a special fuel pressure guage for testing the fuel pressure or will a good air pressure guage work. The fuel pressure valve looks like a air pressure valve.
Thanks for your great support

 

You need a fuel injection gage, Around $20 from Auto Zone. Don't want to chance sparaying fuel all around. Good tool to have in your tool chest anyways. I am assuming you removed the Jeep pump and you are only using the 3.4 pump.